There is known a technology called proxy response. An information processing apparatus includes a main controller and a sub controller. During a sleep mode, a sub controller responds to a query received from an external device connected to a network (so-called proxy response).
During the sleep mode, if the sub controller receives a query of a type that the sub controller cannot respond to that, the sub controller requests the main controller to recover from the sleep mode (to wake up), and transfers the query to the main controller. The main controller recovers from the sleep mode to start the normal mode, and responds to the query. The same applies to a case where the sub controller receives a query of a type that the sub controller cannot determine whether or not the sub controller can respond to that.
From a viewpoint of saving energy of an information processing apparatus, it is desirable for a sub controller to respond to queries of more types without recovering from the sleep mode to start the normal mode.